Pedestrian Dead Reckoning With Smartglasses and Smartwatch

Wearable miniature inertial sensors have been widely used for pedestrian dead reckoning (PDR). Typical low-cost PDR systems use sensors attached to either the human trunk or feet. The recent emergence of smartglasses and smart watches provides an opportunity to use both types of wearable devices in position tracking. This paper proposes a novel method of utilizing both a smartwatch and smartglasses for PDR. The general idea is to use the relative angle between arm swing direction and head direction to detect any head-turn motion that would otherwise skew the position dead reckoning propagation. A complete PDR solution that includes step detection, step length estimation, head-rotation detection, and dead reckoning using a smartwatch and smartglasses that are currently available in the market is presented. Using the smartglasses, step detection with an error rate less than 0.4% and a cumulative distance error of less than 2.4% on 800 m walks and runs is achieved. In the dead reckoning field experiments, the proposed algorithm produces result that closely track the actual path when plotted on Google Maps, outperforming solutions that only use the smartwatch or smartglasses alone.